There is relatively little room for growth in the
overall carpet market, which is tied to the size of the
population. Most who purchase carpet do so only
once or twice, first in their twenties or thirties, and
then perhaps again in their fifties or sixties. Thus as
the population ages, companies producing carpet
will be able to gain market share in the carpet market
only through purchasing competitors, and not
through more aggressive marketing.
Which one of the following, if true, casts the most
doubt on the conclusion above?
(A) Most of the major carpet producers market
other floor coverings as well.
(B) Most established carpet producers market
several different brand names and varieties,
and there is no remaining niche in the
market for new brands to fill.
(C) Two of the three mergers in the industry’s last
ten years led to a decline in profits and
revenues for the newly merged companies.
(D) Price reductions, achieved by cost-cutting in
production, by some of the dominant firms
in the carpet market are causing other
producers to leave the market altogether.
(E) The carpet market is unlike most markets in
that consumers are becoming increasingly
resistant to new patterns and styles.
2．
In comparison to the standard typewriter keyboard, the EFCO keyboard, which places the most-used keys nearest the typist's strongest fingers, allows faster typing and results in less fatigue.Therefore, replacement of standard keyboards with the EFCO keyboard will result in an immediate reduction of typing costs.
Which of the following, if true, would most weaken the conclusion drawn above?
(A) People who use both standard and EFCO keyboards report greater difficulty in the transition from the EFCO keyboard to the standard keyboard than in the transition from the standard keyboard to the EFCO keyboard.
(B) EFCO keyboards are no more expensive to manufacture than are standard keyboards and require less frequent repair than do standard keyboards.
(C) The number of businesses and government agencies that use EFCO keyboards is increasing each year.
(D) The more training and experience an employee has had with the standard keyboard, the more costly it is to train that employee to use the EFCO keyboard.
(E) Novice typists can learn to use the EFCO keyboard in about the same amount of time it takes them to learn to use the standard keyboard.
3．
The recent decline in the value of the dollar was triggered by a prediction of slower economic growth in the coming year.But that prediction would not have adversely affected the dollar had it not been for the government's huge budget deficit, which must therefore be decreased to prevent future currency declines.
Which of the following, if true, would most seriously weaken the conclusion about how to prevent future currency declines?
(A) The government has made little attempt to reduce the budget deficit.
(B) The budget deficit has not caused a slowdown in economic growth.
(C) The value of the dollar declined several times in the year prior to the recent prediction of slower economic growth.
(D) Before there was a large budget deficit, predictions of slower economic growth frequently caused declines in the dollar's value.
(E) When there is a large budget deficit, other events in addition to predictions of slower economic growth sometimes trigger declines in currency value.
4．
Certain messenger molecules fight damage to the lungs from noxious air by telling the muscle cells encircling the lungs' airways to contract.This partially seals off the lungs.An asthma attack occurs when the messenger molecules are activated unnecessarily, in response to harmless things like pollen or household dust.
Which of the following, if true, points to the most serious flaw of a plan to develop a medication that would prevent asthma attacks by blocking receipt of any messages sent by the messenger molecules referred to above?
(A) Researchers do not yet know how the body produces the messenger molecules that trigger asthma attacks.
(B) Researchers do not yet know what makes one person's messenger molecules more easily activated than another's.
(C) Such a medication would not become available for several years, because of long lead times in both development and manufacture.
(D) Such a medication would be unable to distinguish between messages triggered by pollen and household dust and messages triggered by noxious air.
(E) Such a medication would be a preventative only and would be unable to alleviate an asthma attack once it had started.
5．
Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.
Which of the following, if true, most seriously undermines the argument?
(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.
(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.
(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.
(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.
(E) Shungite itself is formed only under distinctive conditions.
和daisyMM指教~！
eople know more about the behavior of other greatly feared animal species, such as lions, alligators, and snakes, than they do about the behavior of bats.